| Step |
Hyp |
Ref |
Expression |
| 1 |
|
lplnneat.a |
|- A = ( Atoms ` K ) |
| 2 |
|
lplnneat.p |
|- P = ( LPlanes ` K ) |
| 3 |
|
hllat |
|- ( K e. HL -> K e. Lat ) |
| 4 |
|
eqid |
|- ( Base ` K ) = ( Base ` K ) |
| 5 |
4 2
|
lplnbase |
|- ( X e. P -> X e. ( Base ` K ) ) |
| 6 |
|
eqid |
|- ( le ` K ) = ( le ` K ) |
| 7 |
4 6
|
latref |
|- ( ( K e. Lat /\ X e. ( Base ` K ) ) -> X ( le ` K ) X ) |
| 8 |
3 5 7
|
syl2an |
|- ( ( K e. HL /\ X e. P ) -> X ( le ` K ) X ) |
| 9 |
6 1 2
|
lplnnleat |
|- ( ( K e. HL /\ X e. P /\ X e. A ) -> -. X ( le ` K ) X ) |
| 10 |
9
|
3expia |
|- ( ( K e. HL /\ X e. P ) -> ( X e. A -> -. X ( le ` K ) X ) ) |
| 11 |
8 10
|
mt2d |
|- ( ( K e. HL /\ X e. P ) -> -. X e. A ) |